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Field Guide to RAPTORS of the Northwest Territories 2 |

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Field Guide to RAPTORS of the Northwest Territories 2 | A Field Guide to RAPTORS of the Northwest Territories 2 | This identification guide includes all species of raptors known to be present in the Northwest Territories. © 2019 Government of the Northwest Territories Recommended citation: Environment and Natural Resources. 2019. A Field Guide to Raptors of the Northwest Territories. Environment and Natural Resources, Government of the Northwest Territories. Yellowknife, NT 39pp. Government of the Northwest Territories (GNWT) would like to acknowledge Gordon Court and Kim Poole for their contribution to this field guide. Funding for this booklet was provided by the GNWT. We would like to acknowledge all those who supported and donated their energy to this project. Maps were created for this project by GNWT ENR based on data from GBIF downloaded in December 2018. See back cover for GBIF resource. The raptor diagram was created for this project by S Carrière (GNWT), based on a photograph by B Turner, used with permission. All photos used with permission. COVER PHOTO: American Kestrel by Gordon Court | 3 Table of Contents 4 NWT Raptor Species Checklist ....................................................................................5 Raptors in the NWT ...........................................................................................................5 Where to Find Them..........................................................................................................5 How to Become a Better Birder ...................................................................................6 Raptor Anatomy ..................................................................................................................7 How to Identify Raptors .................................................................................................. Report your Sightings .......................................................................................................89 How to Use This Guide .....................................................................................................9 Threats to Raptors ............................................................................................................10 Conservation of Raptors .............................................................................................11 Species Information ....................................................................................................... GordonCourt 4 | NWT Raptor Species Checklist The list is organized by Order, then Family. ACCIPITRIFORMES • Turkey Vulture Cathrtes aura CATHARTIDAE ( ) (this species is a vagrant) • Osprey Pandion haliaetus PANDIONIDAE ( ) • Bald Eagle Haliaeetus leucocephalus •ACCIPITRIDAE Golden Eagle Aquila chrysaetos • Northern Goshawk ( Accipiter gentilis) • Sharp-shinned ( Hawk Accipiter) striatus • Cooper’s Hawk Accipiter ( cooperii ) • Northern Harrier Circus ( hudsonius, syn.) Circus cyaneus hudsonius ( ) (this species is a vagrant) • Red-tailed Hawk Buteo( jamaicensis • Rough-legged Hawk Buteo) lagopus • Broad-winged Hawk ( Buteo platypterus) • Swainson’s Hawk Buteo ( swainsoni ) ( ) FALCONIDAE ( ) • American Kestrel Falco spaverius • Merlin Falco columbarius • Peregrine Falcon (Falco peregrinus) • Gyrfalcon ( Falco rusticolus) ( ) ( ) | 5 Raptors in the NWT Raptors are predatory birds that hunt and capture live prey. Some species will also feed on remains of dead animals (carrion). Raptors can often be distinguished by their sharp talons and hooked beaks, which are used for grasping and tearing into their food. Included in this grouping of birds are ospreys, eagles, harriers, hawks, vultures and falcons. Raptors play an important role in our ecosystems. As predators, raptors regulate prey populations and are an essential component of our northern biodiversity. Raptors also have a significant spiritual role and have been an emblem of strength, courage and freedom. The NWT official bird is a raptor: the gyrfalcon! Where to Find Them Raptors are a common sight in many places around the NWT, sometimes year-round. They occur in every habitat. Each map in this booklet shows where a particular species has been recorded in the past. How to Become a Better Birder VIEWING TIPS: Bird watching is about being patient and waiting for the bird. Birds are easily startled by sudden movements and loud noises. If you would like to get a closer viewing of a bird, use binoculars or move slowly and quietly. Each raptor is adapted to a particular habitat. Study their habitat. Wear clothing that blends into the background. 6 | Raptor Anatomy Streaked refer to vertical markings; HEAD Barred refer to horizontal markings. Crown Cere Ear WINGS Mustache Wing Coverts Nape Primaries BODY Breast Back Belly Rump LEGS Thigh Tarsus Talons TAIL Tail Tip | 7 How to Identify Raptors Raptors seem easy to identify, but clearly identifying a species is notoriously difficult. Sometimes, birds are seen only for a fleeting moment, or are flying very high in the sky. Juvenile birds of one species can uncannily resemble the adults of another. Then, like people with different hair colours and outfits, raptors can have “morphs” wherein birds of the same species can differ in plumage patterns and colour. How can some birders distinguish females from males? Females of each raptor species are larger than males. With practice, this size difference will be easier to determine. Experts think the female size difference is an adaptation that allows each member of a breeding pair to share a hunting area without competing for prey, as one can take larger prey species than the other. Another theory is linked to female roles in the pair. Females invest more time during incubation and larger females will be more successful in defending a nest against predators, either from the air Theor ground. Audubon Society gives us great tips to help identify our raptors. • • Relax and do not jump to conclusion about a species right away. • Be humble as the species of distant raptors may be impossible to identify. • Focus on traits you can make out: habitat, shape, motion pattern or wing beats, then general colour or tone, and voice. • Make a mental list of a possible few species and add clues that • eliminate one species at a time. The remaining species is (are) the most probable one(s) you have seen. If you have photos, share them with people and get their opinions. The following are the main traits to look for. This booklet is organized using these groups. Look for more clues in the species pages. This guide has many examples of photos that capture traits to help identify raptor species found in the NWT. 8 | Shape and Motion Group Overall Tail Wings In Motion Vultures Super-size Big but looks Big Will glide for (vagrant) tucked in. hours with Head looks wings in a “V” tucked in too. Osprey Large but Narrow Narrow but Forms an “M” slender (skinny not pointy pattern with as fed on fish) bent wrist Eagles Super-size Big and often Big Will glide for in a fan hours Accipiter Medium -Small Narrow to Short Rapid burst Hawks and steer in forests of flapping, Northern followed by a Harrier glide Buteo Hawks Broad-chested Short Short Spare laboured wing beats Falcons Slender Fast-looking Pointy for Fast, powerful, speed, (sitting) shallow, elastic wings as long wing beats as the tail Report your Sightings https://ebird.org/ canada/home Please report your list of bird species to e-bird ( ). You can also load your photographs on iNaturalist.ca, where other bird enthusiasts [email protected] be able to assist you in confirming the species you have observed.“NWT Report Species” any new species, or new range extension. Send a photograph to or even share it on the [email protected] group . Detailed instructions on how to photograph and record sightings of raptors are also available by contacting us at . | 9 How to Use This Guide Species Pages Species pages follow the checklist at the beginning of this booklet, grouped by Order then Family. Full species pages for vagrant species are not Eachincluded page in willthis have:guide but are referenced. • • • Common name, species scientific name Range map in the NWT • Body size – ranges where lower value applies mostly to males, • the top value to females • Traits • Food • Habitat Breeding periods in the NWT Similar species Threats to Raptors Many raptor populations declined prior to the 1970s due to use of pesticides, such as DDT. Since many countries have banned these types of pesticides, raptor populations have rebounded, demonstrating that environmental damage can be reversed. Ongoing monitoring is required to ensure any impacts of new threats are promptly identified and addressed. Additional threats to raptors that can cause declines include loss of habitat in stopover areas during migration or on wintering grounds, pollution, new types of pesticides, persecution, and collisions with vehicles and man- made structures, such as wind mills. 10 | In addition, the complex effects of a warming climate on our raptors are not well understood. For example, in peregrine falcons, the most studied species of raptors in the NWT, there is evidence that the species is nesting earlier with each decade, presumably responding to climate change. There is also evidence that increased black fly and other insect harassments during brood-rearing period are leading to the mortality of peregrine falcon chicks. How climate change is affecting other species is unknown. Conservation of Raptors Wildlife Act In the NWT, the protects raptor habitat, nesting sites, eggs and
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